Abstract: An RF accelerating cavity includes: a housing having an inner peripheral surface in a tubular shape and conductivity at least on a surface; and accelerating cells inside the housing and each made of a dielectric including, at a central part, an opening through which a charged particle passes. The housing includes a cylindrical barrel portion, with end plates at both ends. The accelerating cells are disposed between the end plates. Each accelerating cell includes: a cylindrical barrel portion having a diameter smaller than an inner diameter of the cylindrical barrel portion of the housing; and a circular disk portion provided inside the cylindrical barrel portion to be fixed to the cylindrical barrel portion, and disposed such that a plate surface is orthogonal to the passing axis of a charged particle, and provided with the opening.

Abstract: An RF accelerating cavity includes: a housing having an inner peripheral surface in a tubular shape and conductivity at least on a surface; and accelerating cells inside the housing and each made of a dielectric including, at a central part, an opening through which a charged particle passes. The housing includes a cylindrical barrel portion, with end plates at both ends. The accelerating cells are disposed between the end plates. Each accelerating cell includes: a cylindrical barrel portion having a diameter smaller than an inner diameter of the cylindrical barrel portion of the housing; and a circular disk portion provided inside the cylindrical barrel portion to be fixed to the cylindrical barrel portion, and disposed such that a plate surface is orthogonal to the passing axis of a charged particle, and provided with the opening.

Abstract: An RF accelerating cavity includes: a housing having an inner peripheral surface in a tubular shape and conductivity at least on a surface; and accelerating cells inside the housing and each made of a dielectric including, at a central part, an opening through which a charged particle passes. The housing includes a cylindrical barrel portion, with end plates at both ends. The accelerating cells are disposed between the end plates. Each accelerating cell includes: a cylindrical barrel portion having a diameter smaller than an inner diameter of the cylindrical barrel portion of the housing; and a circular disk portion provided inside the cylindrical barrel portion to be fixed to the cylindrical barrel portion, and disposed such that a plate surface is orthogonal to the passing axis of a charged particle, and provided with the opening.

Abstract: The present invention provides an accelerating structure capable of increasing a degree of vacuum at a middle part inside the accelerating structure while confining an alternating electric field to the inside. An accelerating structure 1 is formed of a plurality of annular discs 2 and 3 serially connected into a cylindrical shape. At least one of the discs 3 disposed at a middle part of the accelerating structure 1 includes: a choke structure formed by a choke filter 7; and a vacuum port 8 opened in an outer circumferential surface of the disc on an outer circumferential side radially outward from the choke structure, and the vacuum port 8 is connected to an external exhaust device.

Abstract: The present invention provides an accelerating structure capable of increasing a degree of vacuum at a middle part inside the accelerating structure while confining an alternating electric field to the inside. An accelerating structure 1 is formed of a plurality of annular discs 2 and 3 serially connected into a cylindrical shape. At least one of the discs 3 disposed at a middle part of the accelerating structure 1 includes: a choke structure formed by a choke filter 7; and a vacuum port 8 opened in an outer circumferential surface of the disc further on an outer circumferential side than the choke structure, and the vacuum port 8 is connected to an external exhaust device.

Abstract: An HF frequency tuning device includes a resonance cavity in which an HF is introduced, a phase detecting section which generates a sign data representing a sign of a phase difference between a traveling wave and a reflected wave included in the HF in the resonance cavity. The frequency of the HF is repeatedly shifted by a first pitch. The direction of the shift is determined by the sign data for reducing the phase difference. When the sign is inverted, the frequency of the HF is repeatedly shifted to the opposite direction by a second pitch smaller than the first pitch until the sign is inverted again. By this tuning process, the fine tuning of HF can by achieved in a short time.

Abstract: An HF frequency tuning device includes a resonance cavity in which an HF is introduced, a phase detecting section which generates a sign data representing a sign of a phase difference between a traveling wave and a reflected wave included in the HF in the resonance cavity. The frequency of the HF is repeatedly shifted by a first pitch. The direction of the shift is determined by the sign data for reducing the phase difference. When the sign is inverted, the frequency of the HF is repeatedly shifted to the opposite direction by a second pitch smaller than the first pitch until the sign is inverted again. By this tuning process, the fine tuning of HF can by achieved in a short time.